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    Just a simple formula:
   earthRadius_miles &amp;lt;- 3959
   angle_rad &amp;lt;- x/earthRadius_miles
   # Calculate  radius * cord length
   return( earthRadius_miles * 2*sin(angle_rad/2) )
   }
"><meta property="og:description" content="\preformatted{
    Just a simple formula:
   earthRadius_miles &amp;lt;- 3959
   angle_rad &amp;lt;- x/earthRadius_miles
   # Calculate  radius * cord length
   return( earthRadius_miles * 2*sin(angle_rad/2) )
   }
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  <main id="main" class="col-md-9"><div class="page-header">
      <img src="../logo.svg" class="logo" alt=""><h1>Convert surface distance to actual distance</h1>
      <small class="dont-index">Source: <a href="https://github.com/USEPA/EJAM/blob/HEAD/R/distance_via_surfacedistance.R" class="external-link"><code>R/distance_via_surfacedistance.R</code></a></small>
      <div class="d-none name"><code>distance_via_surfacedistance.Rd</code></div>
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    <div class="ref-description section level2">
    <p></p><div class="sourceCode"><pre><code><span id="cb1-1"><a href="#cb1-1" tabindex="-1"></a>\preformatted{</span>
<span id="cb1-2"><a href="#cb1-2" tabindex="-1"></a>    Just a simple formula<span class="sc">:</span></span>
<span id="cb1-3"><a href="#cb1-3" tabindex="-1"></a>   earthRadius_miles <span class="ot">&lt;-</span> <span class="dv">3959</span></span>
<span id="cb1-4"><a href="#cb1-4" tabindex="-1"></a>   angle_rad <span class="ot">&lt;-</span> x<span class="sc">/</span>earthRadius_miles</span>
<span id="cb1-5"><a href="#cb1-5" tabindex="-1"></a>   <span class="co"># Calculate  radius * cord length</span></span>
<span id="cb1-6"><a href="#cb1-6" tabindex="-1"></a>   <span class="fu">return</span>( earthRadius_miles <span class="sc">*</span> <span class="dv">2</span><span class="sc">*</span><span class="fu">sin</span>(angle_rad<span class="sc">/</span><span class="dv">2</span>) )</span>
<span id="cb1-7"><a href="#cb1-7" tabindex="-1"></a>   }</span></code></pre><p></p></div>
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    <div class="section level2">
    <h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">distance_via_surfacedistance</span><span class="op">(</span><span class="va">x</span><span class="op">)</span></span></code></pre></div>
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    <h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2>


<dl><dt id="arg-x">x<a class="anchor" aria-label="anchor" href="#arg-x"></a></dt>
<dd><p>surface distance in miles</p></dd>

</dl></div>

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